He's a longstanding Social Democrat and former board member of Germany's central bank, the Bundesbank, but nowadays Thilo Sarrazin is better known as Germany's bestselling author of a pair of books fiercely criticizing Muslim migration into Germany. The first, "Germany Abolishes Itself" ("Deutschland schafft sich ab"), topped the charts in 2010, while the second, "Hostile Takeover" ("Feindliche Übernahme"), was released this year. 

The second book's release has prompted a third attempt from within the Social Democrats to eject one of their more controversial veterans. So far, the party has not been able to meet its own strict criteria for forcing a member out. 

The party's general secretary, Lars Klingbeil, said on Monday that the SPD's executive board had decided to formally start an expulsion process against Sarrazin based on internal SPD complaints after he ignored its calls to go voluntarily.

Sarrazin, a SPD member since 1973, retorted that the board's move was "part of an inner-party power struggle" over the SPD's future trajectory and denied that his writings were xenophobic.

Read more:  How the press reviewed Thilo Sarrazin's 'Hostile Takeover'

Klingbeil said Sarrazin's book "Hostile Takeover," published in September — which asserts that "Islam hinders and threatens" German society — was not compatible with the SPD's principles and had inflicted "severe damage" on the party.

Inquiry's report under wraps

Klingbeil said that the inquiry panel appointed to scrutinize the book had delivered a "comprehensive and well-researched" report. However, Klingbeil said this report would remain confidential for the time being in accordance with the party's internal arbitration rules.

The party, whose expulsion rules require a high level of proof of damaging behavior, has twice failed to expel the economist and former Berlin city finance senator, but elicited a promise in 2011 from Sarrazin that he would uphold party values.

Bundesbank ouster

In 2010, the Bundesbank sought the economist's departure from its board after the publication of "Germany Abolishes Itself" and after anti-Turkish remarks made during a magazine interview.

The book topped Spiegel's best-seller list for 21 weeks in 2010 and into 2011.

In "Hostile Takeover," his latest book, Sarrazin claims to provide a sober and impartial study of Islam.

Islamic studies experts in Germany quickly decried it as an "absurd" attempt under a "pretense of objectivity" to decipher the Quran without sufficient knowledge of Arabic, theological background, or the impacts of modernity on the religion.

ipj/msh (dpa, AFP, KNA)